Price Manipulation in an Experimental Asset Market

Research, PreprintOPEN

Veiga Helena
;
Vorsatz Marc
(2006)

Publisher: METEOR, Maastricht University School of Business and Economics

Subject: financial economics and financial management ;

We analyze in the laboratory whether an uninformed trader is able to manipulate the price of a financial asset. To do so, we compare the results of two different experimental treatments. In the Benchmark Treatment, twelve subjects trade a common value asset that takes either a high or a low value. Information is distributed asymmetrically, only three outof twelve subjects know the actual value of the asset. The Manipulation Treatment is identical to the Benchmark Treatment apart from the fact that we introduce a computer program as an additional trader. This manipulation program buys a fixed number of shares in the beginning of a trading period and sells them afterwards again. Our results show that the last contract price is significantly higher in the Manipulation Treatment if the asset takes a low value and that there are no price differences between the two treatments if the value of the asset is high. Moreover, this simple manipulation program is, at least in some instances, profitable.